Solar photovoltaic (PV) energy has increased in importance in recent years as a viable alternative to carbon-producing sources of energy. In an effort to drive PV energy towards grid parity, there is a need to improve the power electronics and architecture for grid-connected systems. Traditional PV systems use a central inverter to manage multiple strings of series-connected PV modules. With mismatch among the PV cells, the energy production of the array suffers in several ways: 1) in series strings, current is limited to the lowest-performing cell in the string, 2) if current is forced to exceed this level, external bypass diodes need to turn on throwing away power available in the string and incurring conductive losses, 3) with bypass diodes on, total string voltage may deviate from maximum power voltage (Vmpp), reducing energy production of all modules in the string.
Published in:
Solid-State Circuits Conference Digest of Technical Papers (ISSCC), 2012 IEEE International
Date of Conference: 19-23 Feb. 2012